Scientific Opinion on the substantiation of health claims related to
supercritical CO2 extracted blackcurrant seed oil and maintenance of
normal blood pressure (ID 572) and maintenance of normal blood
LDL-cholesterol concentrations (ID 572) pursuant to Article 13(1) of
Regulation (EC) No 1924/2006[sup]1[/sup]
EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA)2, 3
European Food Safety Authority (EFSA), Parma, Italy
Słowa kluczowe:
Blackcurrant seed oil
LDL
blood cholesterol
blood pressure
health claims
1. Charakterystyka żywności / składnika
The food that is the subject of the health claims is “blackcurrant seed oil (carbon dioxide extracted) + vitamin E”.
From the information provided in the proposed health relationship and wordings, the Panel assumes that the food that is the subject of the health claims is supercritical carbon dioxide (CO2) extracted blackcurrant seed oil (BSO).
Supercritical CO2 is a fluid state of carbon dioxide where it is held at or above its critical temperature and critical pressure. The intention of such an extraction is that the relatively low temperature of the process and the stability of CO2 would allow most compounds to be extracted with little damage or denaturation. Supercritical CO2 extracted BSO contains approximately 47.5 % linoleic acid (LA) (18:2 n-6), 14.5 % α-linolenic acid (ALA) (18:3 n-3), 13.3 % oleic acid (18:1 n-9), 12.6 % γ-linolenic acid (GLA) (18:3 n-6), 5.6 % palmitic acid, 2.7 % stearidonic acid (18:4 n-3), and minor compounds of other fatty acids. It also contains 1.17 % free and esterified phytosterols, mainly sitosterol, 1.28 mg/g α-tocopherol, 0.86 mg/g γ-tocopherol and 0.05 mg/g δ-tocopherol (Tahvonen et al., 2005).
The Panel considers that the food, supercritical CO2 extracted blackcurrant seed oil, which is the subject of the health claims, is sufficiently characterised.
2. Znaczenie oświadczenia dla zdrowia człowieka
2.1. Utrzymanie prawidłowego ciśnienia krwi (ID 572)
The claimed effect is “cardiovascular system”. The Panel assumes that the target population is the general population.
In the context of the proposed wordings and clarifications provided by Member States, the Panel assumes that the claimed effect refers to the maintenance of normal blood pressure.
Blood pressure is the pressure (force per unit area) exerted by circulating blood on the walls of blood
vessels. Elevated blood pressure, by convention 140 mmHg (systolic) and/or 90 mmHg (diastolic), may compromise the normal function of the arteries.
The Panel considers that maintenance of normal blood pressure is a beneficial physiological effect.
2.2. Utrzymanie prawidłowego stężenia cholesterolu LDL we krwi (ID 572)
The claimed effect is “cardiovascular system”. The Panel assumes that the target population is the general population.
In the context of the proposed wordings and clarifications provided by Member States, the Panel assumes that the claimed effect refers to the maintenance of normal blood LDL-cholesterol concentrations.
Low-density lipoproteins (LDL) carry cholesterol from the liver to peripheral tissues, including the arteries. Elevated LDL-cholesterol, by convention >160 mg/dL (>4.1 mmol/L), may compromise the normal structure and function of the arteries.
The Panel considers that maintenance of normal blood LDL-cholesterol concentrations is a beneficial physiological effect.
3. Naukowe uzasadnienia wpływu na zdrowie człowieka
The references provided for the scientific substantiation of the claim included narrative reviews and monographs which referred to the clinical studies provided and described below. Some reviews and non-human studies were provided on the effects of unsaturated fatty acids, particularly of n-3 and n-6 fatty acids. In three human studies, the effects of supercritical CO2 extracted blackcurrant seed oil were investigated.
3.1. Utrzymanie prawidłowego ciśnienia krwi (ID 572)
One randomised controlled trial (RCT) evaluated the effect of 6 g supercritical CO2 extracted BSO consumed daily over eight weeks on resting blood pressure in 28 mildly hypertensive males (Deferne and Leeds, 1996). Subjects received three times per day four gelatine-coated capsules containing either 500 mg BSO (n=14) or capsules with 500 mg safflower oil (control, n=14). One subject dropped out in the control group after five weeks of treatment for reasons unrelated to the study. Resting blood pressure was measured, after an overnight fast, at baseline and weekly for the duration of the study. No significant differences in systolic or diastolic blood pressure were observed between BSO and control groups at any time point during the study. The Panel notes that this study does not show an effect of BSO on blood pressure.
In weighing the evidence, the Panel took into account that the one human intervention study provided, from which conclusion can be drawn for the scientific substantiation of the claimed effect, did not show an effect of supercritical CO2 extracted BSO on blood pressure.
The Panel concludes that a cause and effect relationship has not been established between the consumption of supercritical CO2 extracted blackcurrant seed oil and maintenance of normal blood pressure.
3.2. Utrzymanie prawidłowego stężenia cholesterolu LDL we krwi (ID 572)
A double-blind RCT with a cross-over design compared the effects of 3 g/day supercritical CO2 extracted BSO with 2.8 g/day fish oil on blood lipids in 15 healthy females (Tahvonen et al., 2005). The two treatment periods and the wash-out phase lasted four weeks each. The fish oil contained about 30 % saturated fatty acids (SFAs), 24 % long-chain polyunsaturated fatty acids (LC-PUFAs), 28 % monounsaturated fatty acids (MUFAs), 6 % polyunsaturated fatty acids (PUFAs) and minor amounts of other fatty acids. A 4.9 % reduction in LDL-cholesterol concentrations during the BSO period and a 3.6 % increase in LDL-cholesterol concentrations during the fish oil period were observed. The between-group difference was statistically significant (p<0.05). The Panel notes that the difference in LDL-cholesterol concentrations observed between the BSO and the fish oil interventions could be explained by the different fatty acid composition of the oils (e.g. replacement of SFAs and LC-PUFAs in the fish oil by PUFAs in the BSO oil).
An unpublished manuscript reported on a double-blind, cross-over RCT which compared the effects of 5 g/day supercritical CO2 extracted BSO and of 5 g/day olive oil (about 70 % oleic acid, 15 % SFAs, and 11 % PUFAs, mainly LA) on blood lipids in 12 normolipidaemic males (Johansson, 1999). The treatment periods lasted four weeks each with a wash-out phase of 4-8 weeks in between. The Panel notes the presence of carry-over effects between intervention periods and considers that no conclusions can be drawn from this study for the scientific substantiation of the claim.
No studies, which investigated whether supercritical CO2 extracted BSO has an LDL-cholesterol- lowering effect beyond what could be expected from its fatty acid composition, have been provided.
The Panel concludes that a cause and effect relationship has not been established between the consumption of supercritical CO2 extracted BSO and maintenance of normal blood LDL-cholesterol concentrations beyond what could be expected from its fatty acid composition.
A claim on the replacement of mixtures of SFAs with cis-MUFAs and/or cis-PUFAs in foods or diets and maintenance of normal blood LDL-cholesterol concentrations has already been assessed with a favourable outcome (EFSA Panel on Dietetic Products Nutrition and Allergies (NDA), 2011).
A claim on linoleic acid and maintenance of normal blood cholesterol concentrations has also already been assessed with a favourable outcome (EFSA Panel on Dietetic Products Nutrition and Allergies (NDA), 2009a).
A claim on alpha-linolenic acid and maintenance of normal blood cholesterol concentrations has also already been assessed with a favourable outcome (EFSA Panel on Dietetic Products Nutrition and Allergies (NDA), 2009b).
Wnioski
On the basis of the data presented, the Panel concludes that:
The food, supercritical CO2 extracted blackcurrant seed oil, which is the subject of the health claims, is sufficiently characterised.
Maintenance of normal blood pressure (ID 572)
The claimed effect is “cardiovascular system”. The target population is assumed to be the general population. In the context of the proposed wordings and clarifications provided by Member States, it is assumed that the claimed effect refers to the maintenance of normal blood pressure. Maintenance of normal blood pressure is a beneficial physiological effect.
A cause and effect relationship has not been established between the consumption of supercritical CO2 extracted blackcurrant seed oil and maintenance of normal blood pressure.
Maintenance of normal blood LDL-cholesterol concentrations (ID 572)
The claimed effect is “cardiovascular system”. The target population is assumed to be the general population. In the context of the proposed wordings and clarifications provided by Member States, it is assumed that the claimed effect refers to maintenance of normal blood LDL-cholesterol concentrations. Maintenance of normal blood LDL-cholesterol concentrations is a beneficial physiological effect.
A cause and effect relationship has not been established between the consumption of supercritical CO2 extracted blackcurrant seed oil and maintenance of normal blood LDL- cholesterol concentrations beyond what could be expected from its fatty acid composition.
A claim on the replacement of mixtures of SFAs with cis-MUFAs and/or cis-PUFAs in foods or diets and maintenance of normal blood LDL-cholesterol concentrations, and claims on linoleic acid and on alpha-linolenic acid and maintenance of normal blood cholesterol concentrations have already been assessed with favourable outcomes.